Greening Florida, July 12th

You rightly say reducing car emissions with energy-efficiency measures takes years, but wrongly see difficulties in "changing how individuals behave". One expects The Economist, of all newspapers, to remember the power and simplicity of free markets in changing behaviour. In London, when the mayor took the radical step of asking drivers to pay for the roads they used and subsidized transit—instead of the reverse, as cities like mine do—behaviour changed immediately. Thanks to technological advances from firms like ours, Florida could easily do what London did, and reduce car emissions immediately rather than waiting years.